The present invention relates to internal combustion engines for all present uses including the actuation of vehicles such as automobiles and trucks.
Conventional gasoline fueled "Otto" cycle engines are characterized by approximately an 8 to 1 compression ratio, controlled fuel-air ratio, variable fuel/air charge controlled by the accelerator, variable compression, and combustion pressure and require non-leaded gas to protect the platinum catalytic converter. Each cylinder of a four-stroke cycle engine fires on every other revolution of the crankshaft. Of the fuel used, about 30% of the available energy is lost to jacket cooling, about 30% is exhausted to the atmosphere and the engine is about 27% efficient. The engine requires 80+ octane fuel, has average weight per horsepower delivered, runs well at high rpm and with variable torque, but has poor efficiency, has high air pumping losses for the four-cycle engine and extremely high air pumping losses for the two-cycle engine.
Conventional diesel engines are generally characterized by operation at a compression ratio of about 24 to 1, using a controlled fuel and fixed air charge providing a variable fuel to air ratio and fixed compression pressure with slightly variable combustion pressure. These engines generally require No. 2 fuel oil and fuels. Generally, high NOx gases are emitted. Cylinders of the four-stroke cycle engine fire every other revolution of the crankshaft. About 27% of the available fuel energy is lost to jacket cooling, about 25% is exhausted to the atmosphere and the engine is about 32% efficient. The engine weight per horsepower delivered is relatively high. The engine generally runs poorly at high rpm and runs best at constant torque. Air pumping losses of the four-stroke engine are low and are moderate for the two-stroke engine.
Certain modifications to conventional engines are known. Water injection into the cylinders of internal combustion engines are known such as, for example, the disclosure of U.S. Pat. No. 4,281,626 and the references cited therein. That reference discloses water injection before, at the end of, or after the combustion process.
Fixed early or late intake valve closing is also known, such as, for example, the disclosure of U.S. Pat. No. 4,280,451. That reference discloses fixed intake valve timing set for early closure, before the piston reaches bottom dead center, achieved by shaving the valve timing cam lobe on throttled "Otto" cycle engines. This is said to achieve a lower air charge by always starting the compression of the fuel/air charge at sub-atmospheric pressure, allowing high (13:1) compression ratios without excessive pressure and preignition at the end of the compression stroke.
Firing on demand of four, six or all eight cylinders of a V-8 engine became commmercially available in 1982.
Thermal insulation of internal surfaces of combustion chambers is also know, e.g. U.S. Pat. No. 4,103,655 and presently is in a developmental stage.
The effect of engine gear-down on vehicle braking is kown.
Among the objects of the present invention is the provision of novel engines and related drive devices that improve energy efficiency
Additional objects of the present invention include the provision of engines and related drive devices that are relatively simple to manufacture.
Further objects of the invention will be more fully understood from the following description of several of its exemplifications.